Fat carries flavour, browns food and stops it sticking — but the oil that is perfect for a salad can ruin a sear, and vice versa. Choosing the right fat for the job is one of the easiest ways to cook better. Here is what you need to know.
Smoke Point: The Key Idea
Every fat has a smoke point — the temperature at which it starts to break down, smoke and taste acrid. For high-heat cooking like searing and frying you want an oil with a high smoke point; for finishing and dressing, flavour matters more than heat tolerance. Match the oil to the temperature and you avoid both bitter food and a smoky kitchen.
Common Oils and Fats, and When to Use Them
- Extra-virgin olive oil — lower-to-medium smoke point, big flavour; ideal for dressings, drizzling and gentle cooking.
- Refined olive, avocado and peanut oil — high smoke points; great for searing, roasting and frying.
- Canola / rapeseed and vegetable oils — neutral and affordable, good all-purpose high-heat oils.
- Coconut oil — distinctive flavour, medium-high smoke point; nice for certain bakes and curries.
- Butter — wonderful flavour but burns easily; clarify it or use ghee for higher heat.
- Lard and tallow — traditional animal fats with high smoke points, excellent for frying and pastry.
Refined vs Unrefined
Refining removes impurities that lower the smoke point, so refined oils tolerate higher heat but carry less of their raw flavour. Unrefined and cold-pressed oils keep more character and nutrients but are best kept off high heat. Keep one neutral high-heat oil and one flavourful finishing oil and you are covered for most cooking.
A Word on Types of Fat
Fats are described as saturated, monounsaturated or polyunsaturated depending on their chemistry, and dietary guidance generally favours unsaturated fats for everyday cooking. For balanced, evidence-based information, Harvard’s Nutrition Source is a reliable guide. In the kitchen, variety and moderation serve you well.
A Quick Smoke-Point Cheat Sheet
Rough guide, from lowest to highest smoke point — use it to match oil to method:
- Low–medium (dressings, gentle cooking): extra-virgin olive oil, unrefined nut oils, butter.
- Medium–high (sautéing, baking): coconut oil, virgin olive oil, ghee.
- High (searing, roasting, stir-frying): canola, vegetable, refined olive, peanut, lard and tallow.
- Very high (deep-frying): refined avocado, refined peanut, sunflower.
Reusing Frying Oil
Oil used for deep-frying can often be reused a few times if you treat it well: let it cool, strain out food debris through a fine sieve or muslin, and store it airtight in a cool, dark place. Discard it once it darkens noticeably, smells off, foams, or smokes at a lower temperature than before — all signs it has degraded.
Storing Oils So They Last
Heat, light and air turn oils rancid. Store them in a cool, dark cupboard, keep lids tight, and buy delicate oils in quantities you will use within a few months. If an oil smells sharp, waxy or like old crayons, it has gone off — replace it. Fresh oil simply tastes better and treats your cookware more kindly too.